The invention relates to a locking arrangement for locking a door hinged to a casing by means of a combination or key lock, and of the kind comprising a rotatable closing rod for keeping the door closed by engaging the casing in a closed position; a fitting having a U-shaped part encompassing at least a length of the closing rod; two flushing locking holes made with one hole in each of the opposite walls of the U-shaped part; a transverse hole made in the closing rod and flushing with the locking holes in the closed position; and a bolt having a first section provided with a head, and a second section mounted in the lock displaceable between a locked inner position and an unlocked outer position; whereby the locking arrangement is locked when the bolt is extending through the transverse hole and the locking holes in locked inner position.
Such a locking arrangement is known from U.S. Pat. No. 6,442,982, the entire disclosure of which is expressly incorporated herein by reference in the present description. This known locking arrangement is intended e.g., for containers that are to cross country borders, and the locking arrangement is therefore sealed by a seal that is broken at customs checks.
In this case, the seal consists of an integrated head on the bolt. Near the head, the bolt can be designed with a break indicator in form of a circumferential weakening groove allowing the head to be cut or broken off. Alternatively, the head is cut off by means of a bolt cutter or is sawn off.
As the head cannot get through the holes of the locking arrangement, the bolt has to be pushed through the holes from one side of the fitting in order to be able to engage the lock on the other side of the fitting. During this, the second end part of the bolt could pick up impurities which it will carry along into the lock upon assembling, just as moisture could enter the lock when the bolt is pulled out. The impurities and the moisture could damage or ruin the delicate locking mechanism of the lock.
When the door is to be opened, the lock is unlocked whereby the bolt automatically is driven out into the outer position by a spring. Then, the head is removed in one of the above-mentioned ways, the broken bolt pulled out of the holes of the locking arrangement together with the lock, and the closing rod rotated free of its engagement with the closing rod, after which the door can be opened.
When the door is to be sealed again, the broken bolt is removed from the lock which is assembled with a new bolt in the way described above.
This process normally takes place many times during the life of the locking arrangement at the risk of the lock gradually starting to malfunction. As the locking arrangement in itself is burglarproof, the very serious problem might arise that it will not be possible or at least be very difficult to obtain access to the content in the full container. Accordingly, improvements in these type devices are desirable, and they are now provided by the present invention.